Purpose: To investigate the efficacy and side effects of two different intravenous immunoglobulin (IVIG) dose regimens for the initial treatment of childhood acute immune thrombocytopenic purpura (ITP).
Methods: Thirty-four consecutive patients with a clinical diagnosis of acute ITP and a platelet count below 20x10(9)/L were randomized to receive either 1 g/kg body weight (n=17; group A) or 0.3 g/kg body weight (n=17; group B) IVIG per day for 2 consecutive days (total dose 2 g/kg and 0.6 g/kg).
Results: Fifteen of the 17 patients (88.2%) in group A and 13 of the 17 patients (76.5%) in group B achieved a platelet count of more than 20x10(9)/L within 72 hours. The increase in platelet counts on day 2 and 3 was more pronounced in the high-dose group. Two patients in the high-dose group and four in the low-dose group were non-responders. Chronic disease occurred in three patients receiving 2 g/kg IVIG and in five patients receiving 0.6 g/kg IVIG. Side effects of IVIG administration were more common in the high-dose group.
Conclusions: The present study showed that platelet counts increased more rapidly after high-dose IVIG administration within the first 72 hours, although a platelet count of more than 20x10(9)/L can be achieved also with low-dose IVIG in most children with acute ITP. For patients with very low platelet counts, doses higher than 0.6 g/kg seem, therefore, to be more effective.